They are not stars... he's posted a 300s dark frame with the cooling turned off
haha!
In all seriousness...
Niiiiice!!
A real eye opener... You know, you hear it a lot, that there is more stars in the universe than there is grains of sand on earth... Never before have I seen an image that makes you say "yep... I would agree with that!"
Great variation in star colour in there too..